Networking Trends: Ethernet, wireless and traditional serial devices
Prospects for continued adoption of device-level factory automation networks remain overwhelmingly tempered by the weight of current and future economic pressures felt by OEM machine builders and end users.
Within the factory automation marketplace itself, however, continued growth in device network adoption will be primarily determined by the rate at which networked solutions displace conventional hard wiring schemes, a primary value proposition at this level. The worldwide market for factory automation networks at the device level will decline this year but is expected to strongly rebound in 2010, according to a new ARC Advisory Group study.
The emphasis on displacement of existing schemes is true not only for networked versus hardwired solutions, but also within the factory network realm itself. For example, much of the growth in Ethernet-based device networks results from successful competition against traditional serial device networks. “In some quarters, the growing movement toward a single network technology throughout the plant or enterprise increasingly overshadows the compelling wiring savings delivered by traditional serial device networks,” according to ARC vice-president Chantal Polsonetti, the principal author of ARC’s “Factory Automation Networks Worldwide Outlook.”
Value Propositions Vary Across Network Types
Device-level factory automation networks continue to provide a significant value proposition in their served markets, and the total available market (TAM) for potentially attached devices and I/O remains unsaturated. Wiring displacement remains a primary driver for the traditional serial device networks, while wireless device networks represent not only “the ultimate fieldbus” from the perspective of wiring savings but also enable mobility, portability, remote access, and other incremental benefits relative to traditional serial device networks.
The reduced wiring value proposition is less true with industrial Ethernet installations, however, where the standard hub-and-spoke topology off-sets any potential for wiring savings. Ethernet’s rising popularity in spite of this shortcoming highlights the higher-order value propositions, including integration with higher-level enterprise systems, sought by some device level network adopters.
The Role of Common Network Protocols
While factory automation suppliers must keep pace with the migration of network technology toward each new physical medium — Ethernet, wireless, etc. — the competitive advantage, and increasing basis of competition, lies in the upper layers of the OSI network stack. Ability to port a media-independent protocol across a variety of network types delivers numerous advantages in key areas such as software tools, command sets, human-machine interface, ease of integration, upgradeability, support base, and others.
Convergence around a common protocol similarly makes it easier to add incremental application-specific profiles as the need arises and to expand the application base. In the current discrete market, this is particularly true in areas such as motion control and functional safety, with many of the existing network promoters adding profiles that allow them to deliver this functionality and meet emerging industry standards.